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The Cropwalker - Volume 2 Issue 37

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Crop Conditions

Corn – continues to slowly develop. More fields dented now. Probably 60 % 0f acres are dented. Soybeans first acres are off. One field in Clinton area of S03W4 yielded about 45 bu/ac which is 80-85% of the yield normally on this variety by this grower. Another grower further south had 70 bu/ac off 170 acres. This is above his long-term average. They received timely rains. Provincially, probably 60% of fields have started to turn colour. Still a Way to go. Winter Wheat seeding has started. Fields that received rain after seeding will jump out of the ground. Forages – harvest continues through what we used to call “Critical Harvest Period”, but as we saw last year it didn’t matter whether you harvested during this period. As I drive around, I see a lot of alfalfa fields that have seriously thinned out. I am concerned that their owners believe they will somehow thicken over winter. They won’t. Manure - consider spreading as much manure as possible now when ground is dry rather than waiting. Then you can spread more later. Experience has shown that you can spread liquid dairy manure on new alfalfa seeding this year.


Should I Apply Nitrogen this Fall with Winter Wheat

Nitrogen encourages fall tillering. Typically, wheat produces two to three more tillers than it needs. I think if we can have those tillers more advanced this fall, there will be more even heading next year. Also, estimate about 50% of the nitrogen you apply this fall will still be there next spring. This allows you to delay spring nitrogen applications without fear of losing yield. Many years you cannot get nitrogen on wheat when you want to due to weather conditions.

Value of Corn Silage

Have had some more questions. Here is what we agreed in one case. Presume corn will yield 150 bushels dry. The price per bushel is $5.00 /bushel. This is $750 per acre standing. Some corn will be left for grain to verify yield. Buyer harvests corn. Owner has no charge for harvesting, drying, trucking, elevation. Seller has agreed to buy back some manure. If yield is different than 150 bu/ac there will be a recalculating. If you cannot agree to $5.00 then agree on dollar/bushel as established by Agricorp.

Significance of late Crop Heat Units (CHUs)

The CHUs we are collecting now are not as valuable as those collected in August. CHUs are calculated by measuring day and night-time temperatures. BUT corn growth is determined by heat, and, the number of hours and intensity of sunlight. With shorter days we can collect CHUs at the same rate as if these temperatures were in August, but we have less sunlight. As a result the CHUs in late September, do not produce as many carbohydrates (yield) as if they occurred in August. Bottom line, this will affect yield. We all have seen corn yield projections of an average yield of 173 bu/ac. The 5-year average for corn is 164.6 bu/ac, based on OMAFRA numbers. The 5-year average yield for soybeans is 46.9 bu/ac. Probably realistic yields for Ontario is 150-156 for corn bu/ac, and, 40-42 bu/ac for soybeans.

Corn Yield Loss from an Early Frost – This table gives an approximation of yield loss due to an early frost. There is a difference among hybrids. Also, frost can be worse in areas of the field so this will be reflected in different losses in different parts of the field. (Table from OMAFRA Pub 811)

Table 1 - Corn Yield Loss due to Frost Prior to Black Layer

Corn Test Weights (TW)

A standard bushel of corn occupies 1.224 cubic feet. Long ago, it was decided this should weigh 56 pounds. (Even though there is a lot of variation in the weight of 1.224 cu ft. of corn.) With a higher test weight, yield is higher even though volume is not higher. How often has some one commented on there being more weight on this truck or wagon than normal. This year a standard volume may weigh less. There is no co-relation between yield and bushel weight. The minimum for grade two is 333 gm/0.5 L. This equates to 53 pounds/ bushel. If you have 56-pound bushel weight corn this is 353 gm/0.5 L. Kernel size, shape, and density all affect TW. Higher TW means better filled kernels, with a higher percentage of hard endosperm. Low TW frequently implies that the crop did not mature entirely, or that it was subjected to stress conditions. Right now, I think this year’s corn yield will be held back because of TW. (There will be a lot of #2, but not a lot of 58+ lb. bushel weight corn.) Dry corn TW of 52-54 pounds/ bushel (compared with the more typical 55-57 pounds/ bushel are indicative of incomplete maturity. Ethanol processors may not be greatly affected by lower test weight. Lower protein, and higher starch yields more ethanol, but does reduce DDGs quality. The feed value on a weight, not volume, basis of low-test weight corn is nearly equal to normal corn. Light corn will break more easily and create more fines in storage. Corn grain is marketed based on a 56 pound "bushel" regardless of test weight.

How Do I Control Volunteer Wheat in Summer Seeded Alfalfa?

If you have significant volunteer wheat, especially behind the combine, you can spray with Venture or Poast Ultra or Select. Assure is not registered for alfalfa for forage. This will take out any seedling grasses, so it will only work on pure alfalfa stands.

Picture 1 - Volunteer Wheat in New Seeding Alfalfa

Cold Sensitive and Cold Tolerant Weeds – Purdue researchers suggest that weeds are either cold sensitive or cold tolerant. Cold sensitive weeds do not readily take up herbicides after a light frost. Weeds in this group include dogbane, (looks a bit like milkweed), milkweed and bindweed. Spray these before a frost. Cold tolerant weeds take up more herbicide after a good frost. The frost triggers the plant to store more nutrients. Thus, herbicides are translocated more/better than before a frost. Weeds in this group include dandelion, wild carrot, and quack grass. Spray these weeds three to four days after a heavy frost. Consensus is that perennial sow thistle is neither cold sensitive, nor cold tolerant. From my experience perennial sow thistle can be controlled any time now if you have actively growing rosettes. All of this must be practical. You cannot wait forever to get all the spraying done. If you spray and work the ground generally kill is improved.

Do I need to do a pre-harvest application on soybeans?

Assuming you have controlled any weeds of concern as far as harvestability, it then depends on two factors, if the field is going to winter wheat, and if you are going to do tillage.

If you have perennial weeds (dandelions/sowthistle) or biennials (burdock) with green plant tissue, you should do a pre-harvest application with 0.67 L/ac of 540 gr/L glyphosate (if your elevator/end-user allows you), regardless of whether you are seeding winter wheat or doing fall tillage.

If you have winter annuals, such as Canada fleabane, chickweed, field violet, speedwells, etc. and you are going to winter wheat, you should do a preharvest application, if doing fall tillage, no burndown is required (provided the tillage will control the fleabane).

Picture 2 - Mature Perennial Sowthistle in Soybeans
Picture 3 - No weeds above canopy does not mean no Pre-Harvest
Picture 4 - Weeds in canopy may determine pre-harvest needs

When should I do my fall stubble burndowns?

Only two reasons to delay fall burndowns, 1) you have a field that historically has a high number of winter annuals, and, will not be doing fall tillage. 2) you have a cover crop and would like to maximize biomass.

How much sulphur will be available the following spring from MESZ?

Microessentials SZ (MESZ) from Mosaic is half sulphate sulphur and half elemental sulphur. The elemental sulphur portion release is controlled by three factors; soil pH, soil temperature, and soil organic matter. At one time Mosaic had assumed it was all released within one growing season, but this was based upon a study at a constant soil temperature (growth chamber) and does not reflect field conditions. As a rule of thumb, I would expect you to have 60-75% of the total sulphur available for the following growing season (if fall applied).

I’m currently using MAP for my wheat starter, when could I expect to get a response to using MESZ?

I would expect that you would see a response to MESZ in fields that; 1) you see a sulphur response in other field crops, 2) fields that see a response to zinc in corn. 3) soils with low organic matter levels.

Critical Relative Humidity in Fertilizer Blends

Seemed like every fall you would get a call; “What is this $#*! you sent me?” Then looking at the critical relative humidity chart, and seeing what the grower was trying to do, it simply wasn’t possible to do in an aircart in damp conditions. If you are thinking of using a blend through the aircart this fall, please check the relative humidity chart, and make note of any watch outs. Dusty product will compound the problem, as there is much more surface area to pick up moisture.

Graph 1 - Fertilizer Relative Humidity Chart from TVA
Graph 2- Fertilizer Material Compatibility Chart (EFMA)

Don’t harvest overly dry soybeans, it costs!

When you deliver grain under the moisture of commerce, it will cost you in total revenue. You are paid on weight, not the number of bushels. Take a look at the chart below, and why you should try and avoid harvesting overly dry soybeans.

Table 2 - Overly Dry Soybean Moisture Impacts Revenue

Can I afford to upgrade spreaders?

I had commented last week to someone that, if you farm significant acres, and/or apply dry fertilizer to cereals, you cannot afford to spread fertilizer without section control. I usually figure you can take what you save from section control and double it, as there will be some improvements on yield as well (especially in cereals). As well, in the past, there has been some cost-share grants available through LEADS or CAP for these types of units. Will have to see in the next in-take program if there are funds available.

Here is an example calculation for a 1,000-acre farm with a 1/3 corn, 1/3 wheat and 1/3 soybean rotation. I assumed they used dry fertilizer on all the crops, and applied crop removal, and an overlap rate of 3%, which is on the low side for overlap.

Picture 5 - Section Control on a European Designed Spreader
Chart 3 - Section Control Analysis on 1000 acres

I stand corrected…

There are North American made spreaders with section control. Two manufacturer examples are Salford’s BBI Sniper has 12 sections, and the BBI Magnaspread line has left/right (2 sections); New Leader’s G5 commercial application box has 16 sections. If you are in the market for a spreader, look at the available options on the market, and ask if they have section control capability.

Roundup Pre-Harvest Staging Guide

Can be found at this link;


"Calvin: They say the world is a stage. But obviously the play is unrehearsed and everybody is ad-libbing his lines.

Hobbes: Maybe that’s why it’s hard to tell if we’re living in a tragedy or a farce.

Calvin: We need more special effects and dance numbers."

- Calvin and Hobbes